A smarter approach to multi-source wastewater treatment in the Czech Republic

Advanced modelling of municipal, industrial and landfill leachate wastewater to boost performance, efficiency and cost savings

Vodovody a kanalizace Pardubice, a.s. (VaK Pardubice) operates a complex wastewater treatment plant handling municipal and industrial wastewater. The plant faced challenges from fluctuating industrial inflows and costs associated with chemical dosing and aeration. Working with DHI, VaK Pardubice automated data processing and developed a calibrated mathematical model of the plant, including specialised modules for industrial wastewater neutralisation and heavy-metal treatment. DHI’s solution revealed ways to simplify operations, reduce chemical and aeration energy use, lower costs and improve effluent quality, while providing a practical tool for faster, more confident operational decisions.

Challenge

Due to the high complexity of the wastewater treatment system, VaK Pardubice needed to map plant operations and identify opportunities to improve performance, increase treatment efficiency and reduce operational costs. The plant faced multiple challenges, including highly variable industrial influent that had to be neutralised in dedicated tanks, with the fate of metals depending on this process. The WWTP also handled municipal wastewater and nitritation of landfill leachate, adding further complexity.

While detailed data on water and sludge quality were collected at each treatment unit, manually evaluating the system and understanding the interactions between units was extremely time-consuming. Significant operational costs also arose from the continuous need for chemical dosing and aeration. Although large volumes of operational and quality data had been systematically collected over the years, manual evaluation remained impractical due to system complexity and dispersed data. These challenges, if unaddressed, could result in lower treatment efficiency, higher emissions and negative impacts on the surrounding environment and residents.

Solution

To address the plant’s challenges, VaK Pardubice worked closely with DHI to thoroughly review how the WWTP and its main units were operating.  Data from the plant’s monitoring system and laboratory analyses were collected, organised and combined into a single dataset using a custom-made script in Python, providing a clear overview of plant performance. Key inflow and outflow points were identified, and a technological scheme of the plant was created to serve as the basis for further analysis.

With this foundation, DHI developed a mathematical model of the entire WWTP, using three years of historical data to ensure the model closely reflected existing conditions. What made this solution unique was the development of a detailed neutralisation and heavy metals precipitation model. Additionally, the semi-continuous batch reactor (SBR) block in WEST was modified to reflect the specific operational regime of the SBR unit for landfill leachate treatment in Pardubice. 

Other simulation tools could have been applied, but none would have matched the detail and flexibility achieved with WEST. Drawing on its extensive experience, DHI was able to develop the new model blocks seamlessly, giving the plant a powerful decision-support tool to streamline operations, potentially cut costs and boost performance.